Introduction - Electrical Land Rover Range Rover III

General

This document is intended to assist in diagnosing electrical faults, and should be used in conjunction with the Electrical Circuit Diagrams. The document is divided into the following sections.

1. «INTRODUCTION»(/land-rover/range-rover/iii-2002-2005/remont/electrical/#introduction-electrical) - Includes Electrical Precautions, a list of Abbreviations and general information on how to use this document.
2. «FUSE DETAILS»(/land-rover/range-rover/iii-2002-2005/remont/electrical/#introduction-electrical__fuse-details) - Provides details of location, rating in Amperes, and circuit(s) protected.
3. «EARTH POINTS AND HEADERS»(/land-rover/range-rover/iii-2002-2005/remont/electrical/#introduction-electrical__earth-points-and-headers) - Provides details of earth points and earth headers, including a plan view of the vehicle to aid location.
4. «DESCRIPTION AND OPERATION»(/land-rover/range-rover/iii-2002-2005/remont/electrical/#introduction-electrical__description-and-operation) - Provides an explanation of how each of the systems operate.
5. «CONNECTOR DETAIL»(/land-rover/range-rover/iii-2002-2005/remont/electrical/#introduction-electrical__connector-details) - Details of connectors including a location photograph, face view and pin-out table.

Note. Before starting electrical checks on the vehicle, ensure that relevant mechanical functions operate satisfactorily.

References

References to the LH or RH side given in this document are made when viewing the vehicle from the rear.

Operations covered in this document do not include reference to testing the vehicle after repair. It is essential that work is inspected and tested after completion and, if necessary, a road test of the vehicle is undertaken, particularly where safety related items are concerned.

The following guidelines are intended to ensure the safety of the operator whilst preventing damage to the electrical and electronic components fitted to the vehicle. Where necessary, specific precautions are detailed in the relevant sections of this document, reference to these precautions should be made prior to commencing repair operations.

Equipment - Prior to commencing any test procedure on the vehicle, ensure that the relevant test equipment is working correctly and any harnesses or connections are in good condition. This particularly applies to mains lead or connections.

Polarity - Never reverse connect the vehicle battery and always observe correct polarity when connecting test equipment.

High Voltage Circuits - Whenever disconnecting live ht circuits, always use insulated pliers and never allow the open end of the ht lead to come into contact with other components, particularly ECU's. Since high voltage spikes can occur on the terminals of the coil while the engine is running, exercise caution when measuring the voltage at these points.

Connectors and Harnesses - The engine compartment of a vehicle is a particularly hostile environment for electrical components and connectors. Always ensure these items are dry and oil free before disconnecting and connecting test equipment. Never force connectors apart either by using tools or by pulling on the wiring harness. Always ensure locking tabs are disengaged before removal and note orientation to enable correct reconnection. Ensure that any protective covers and substances are replaced if disturbed.

Two Land Rover harness repair kits are available. Range Rover (LM) harness repairs can be carried out using repair kit LRT-86-010. Range Rover (LP), Discovery Series II, and Freelander (01MY onwards) are covered by Harness Repair Kit LRT-86-010/1.

The Harness Repair Kits contain the following components to enable the technician to carry out 'Right First Time' repairs

z Crimping pliers.

z Wire cutter/stripping tool.

z Heat shrink tubing.

z Wire color identification rings.

z Splice connectors.

z Pre-terminated leads (connector pins with 90 mm wire 'pig tails').

z Connector housings.

z Connector pin extractor tools.

Note. Replacement connector housings and pre-terminated leads can be ordered from: SPX UK Ltd, Genoa House, Everdon Park, Daventry, Northants, NN11 5YJ. Tel: +44 (0)1327 303400.

In order to carry out a repair, a suitable hot air gun and heat resistant blanket will also be required. These can be sourced locally.

The kits can be used to make repairs to all except the following

z Any Media Orientated System Transport (MOST) network harnesses.

z Supplementary Restraint System (SRS) firing circuits.

z ABS wheel speed sensors with molded connectors (Discovery Series II, and pre-02MY Freelanders only).

z Any wires with a Cross Sectional Area (CSA) of greater than 4.0 mm2.

If damage occurs in any of these areas, an overlay harness must be used.

ABBREVIATIONS

Fuse Details

Contains information on fuse functions and values and should be used together with the power distribution circuit diagrams to establish which systems share a common power supply and to ensure that correct value fuses are fitted.

Earth Points and Headers

Shows a plan view of the vehicle with location of all earth points. Supporting photographs and connector detail information appear in the Connector section.

Description and Operation

Presented in the same order as the circuit diagrams in the Electrical Circuit Diagrams publication, each of the descriptions contains a brief overview of the main system functions and includes reference to the appropriate wire colors. Always read this section before starting work on a system so that a good understanding of system functionality is obtained.

Connector Details

This section is effectively an index of every electrical connector on the vehicle, including headers and eyelets. A page is dedicated to each connector, with the information presented in a standard format. The connector number is displayed on each page header to ease reference. Connector information comprises

z Connector Number - The assigned number, prefixed 'C'.

z Connector Name - Usually derived from the component to which the connection is made.

z Male/Female - If applicable, identifies the gender of the connector pins (NOT the housing) as Male or Female. Generally, connectors mating directly into a component have Female pins.

z Color - If applicable, the color of the connector housing is shown. NATURAL is used to describe connectors with a clear/translucent plastic finish.

z Location Statement - Used in conjunction with the photograph to determine the location of the connector.

z Photograph - Shows the location of the subject connector. In most cases the photograph will indicate the amount of trim removal necessary to reveal the connector.

For convenience some photographs identify more than one connector.

z Face View - An outline of the connector housing, viewed from the front, showing pin numbers (if applicable).

z Ways - This identifies the number of cavities within the connector.

When diagnosing an electrical fault, follow the steps below

1. Read the circuit description appropriate to the reported fault to ensure a good understanding of circuit operation.
2. Study the power distribution, fuse details and earth distribution diagrams and identify other circuits which share fuses and/or earth points. Check whether these circuits operate correctly.
3. Using the photographs contained in the Connector section, locate a point on the circuit (approximately half way between supply and earth) which is easily accessible.
4. Check that the pin-out details of the connector are correct and that the correct signals exist at the correct terminals.
5. Using a suitable non-permanent marker, mark the parts of the circuit you have verified.
6. Continue to the next point on the circuit which is easiest to access and repeat the above.
7. Continue with this approach until a fault is found, rectify the fault and then verify that the circuit operates correctly.

Never probe wire insulation. On small diameter cables this can cut the conductors. It may also allow moisture into the cable, causing corrosion.

The following list contains wire color codes used on the vehicle harness's.

WIRE COLOR CODES

See also:
• GENERAL INFORMATION
• INTRODUCTION
• FUSE DETAILS
• EARTH POINTS AND HEADERS
• DESCRIPTION AND OPERATION
• CONNECTOR DETAIL